Radiator pressure cap



July 4, 1939 J. E. ESHBAUGH ET AL 2,154,450

RADIATOR PRESSURE CAP Filed Dec. 30, 1937 Patented July 4, 1939 PATENT OFFICE RADIATOR PRESSURE CAP Jesse E. Eshbaugh and Nelson Walker, Flint, Mich., assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application December 30,1937, Serial No. 182,414

8 Claims.

erated valving which serves to reduce loss ofA cooling liquid.. The parts are few in number and in the main are inexpensive easily formed sheet metal stamplngs`which can be put together in a simple fashion and kept in good working order. Furthermore the parts are designed to be positive in action without the need for extreme accuracy in manufacture, thus promoting economic large quantity production.

For a better understanding of the invention reference' may be made to the accompanying drawing wherein Figure 1 is a side elevation of a portion of an engine cooling system; Figure 2 is an enlarged sectional view of the filler spout construction; Figure 3 is a fragmentary sectional 2,) view showing a modication; Figure 4 shows in side elevation the upper portion of the spout andy Figure 5 shows a detail. Y

In the drawing the jacketed cylinder block I is shown with the usual outlet connection 2 with the lower or outlet header 5 has a return connection 6 to the water pump 'I for circulating the cooling medium through the system. The pump 'I -is driven from the engine. crankshaft by a belt 8 which also drives the fan 9 for drawing cooling air through the radiator core. As is customary the inlet header 3 is provided with a filling spout as at III from which leads intermediate its height an overilow or vent pipe II. The lower or inner end of the filling spout has an inturned ilange I2 to be mounted on the top wall of the tank 3 with a downwardly curved internal seat I3 dening an opening alined with an opening in the tank wall and affording a valve seat.

At its upper end the spout wall is turned outwardly and is provided with a raised annular ridge I4 providing a seat'for the peripheral porton of a spring disk or sealing diaphragm I5 and the outturned annular ange terminates in a downwardly directed skirt as at I6. metrically opposite points both the outturned ange and downturned skirt are providedwith entering slots as at Il for a pair of internal fingers I8 punched inwardly from the stamped 50 cap I9 for cooperation with the lower edges of the skirt portions I6 in affording a bayonet type connection between the spout and cap. As ishown particularly in Figure 4 the lower edge of each rim portion I6 on which fingers I 8 ride is in the nature of a stepped cam whereby upon rotation top or inlet header 3 for the radiator core 4. The

At dia? (Cl. 22o-44) v of the cap the camming abutments cause a concurrent axial movement of the cap assembly on the spout. Dependent tongues as at ISa constitute stops which define the nal seated position of the lingers I8 and the step in each con- 5 toured ramp, asshown at 20, is located adjacent the entering slot Il and constitutes a safety stop as will be later referred to.

To afford working clearance between the cap I9 and the spring diaphragm I5 the central portion 1" of the cap is depressed as at 2l aording a spacer boss to which the central portion of the disk is firmly secured in non-rotatable relation to the cap, between the boss and a shoulder on a dem pendent studY 22 whose upper end is riveted or peened over at 23 to afford a secure mounting. Optionally the rivet stud may also locate a cupped wear plate 24 for one end of the valve seating coil 'spring 25. In some instances the 4 cupped plate 24 may be entirely omittedwith the 9" spring 25 then seating directly 'against the underside of the disk I5. The dependent stud 22 termnates in an enlarged head 26 or other form of retainer which mounts on the stud a domed valve. to be held by the'spring 25 against the `-'--5` annular curved seat I3. This valve includes the cylindrical portion 21 extending internally of the coil spring25 and terminating at its upper end in an inturned flange 28 loosely and slidably tted to the stud 22 within the limit dened by the retainer head 2li.l

At its lower end the cylindrical or tubular portion 2l terminates in an outwardly and upwardly Haring flange 29 which may be either of frustoconical shape or of curved shape in section and 5'- which forms a backing for a similarly shaped sealing gasket 30 for substantially line engagement with the curved valve seat I3. Because of the relation of the valve and seat and the sloppy connection between the stud 22 and the inturned ange 28 at the upper end of the domed valve member, a tight seal and a self-centering action is insured. The loose mounting also allows relative pivotal action, whereby scrubbing and wear between the valve and its seat is reduced since cap rotation does not carry with it the seated valve.

The gasket 30 is retained in position by an outturned flange 3| of a second dome-shaped member whose cylindrical wall 32 has a press t or is "i otherwise securely held interiorly of the'wall 2l, whose upper end'is iianged inwardly and then centrally depressed and apertured to form a valve seat 33. As shown in Figure 2, the cooperating valve which consists of a gasket 34 and a backing 5;;

ondary valve within the centrally domed portion of the main valve but in normally open position. In this case the C-shaped retainer 38 is formed as shownrin Figure 5 softhat spaces between its straight portions and the cylinder 32 provide breathing passageways around the valve for communicating the system with the overflow vent With the arrangement of Figure 3 the system normally is in free communication with atmosphere and avoids compression of vapors within the system and a bulging pressure on the radiator core, as the body of liquid warms up. However, should a sudden liquid surge occur the moving body of liquid will raisev the valve to its seat thereby resisting expulsion of the liquid and upon the subsequent recession of the pressure pulsation, the valve immediately opens to relieve any suction effect and avoid bursting strains on the hose connections and fragile core assembly. However, in the event the pressure rise internally of the system exceeds the forceV of the spring 25 the valve assembly will raise from its seat to relieve the excess pressure. Where the inwardly opening valve normally is closed, as is the case in the Figure 2 embodiment, the excess internal pressure similarly opens the main valve but the system ordinarily operates under slight pressure as a result of heat expansion of the liquid. As the liquid cools down and contracts in volume, the internal depression causes the secondary valve to open against the pressure of the spring 36 for an approximate balance of pressures.

The relation of the retainer head 26 and the inturned flange 28 of the valve assembly is such that if the cap is to be removed, its backward rotation and concurrent outward movement toward the position wherein the fingers I8 engage with the safety stops 20, will cause the head 26 to engage with the ange 28 and lift the gasket 30 off the seat I3 for free communication of the system through the overflow. pipe. By this means internal pressure is relieved prior to complete removal of the cap and the person removing the cap after noting that the internal pressure has been relieved may then depress the cap slightly moving the fingers I8 inwardly to clear the stop 20 and complete the detachment of the cap from the spout. This safety feature insures against accidental injury by scalding or otherwise.

From the above description it will be seen that the arrangement of parts is such that cost may be reduced to a minimum and that the parts may be easily kept clean and in good working order.

We claim:

1. In an engine cooling system, a fillerspout having a pair of spaced seats and a 4vent between said seats, a spout closure including a cap, a spring disk beneath the cap sealingly engaging at its periphery with the outermost seat, a rivet stud projecting centrally through and securing together the disk and the cap and having a dependent headed stud, a tubular element having an upper inturned flange loosely and slidably carried on said stud above the stud head and a.

lower outturned flange adapted to seat on the innermost spout seat, intercngaging camming retainer abutments on the cap and spout, respectively, adapted upon relative rotation of the cap to move the same axially of the spout, said abutments and headed stud being so constructed and arranged that outward movement of the cap through said abutments, brings the stud head into engagement with said inturned flange to lift the tube and said outturned flange off the innermost seat.

2. In a radiator pressure cap of the character described, a retainer cap member, an outer spout engaging seal carried by said member, a dependent stud centrally secured to the cap and mounting the seal thereto, a spout engaging pressure opening valve having a centrally domed portion slidably tted to the stud, a retainer head on the stud to engage said domed portion, and a pressure closing valve housed within said domed portion.

3. In a iilling spout closure of the character described, a retainer cap having a centrally dependent stud, an outwardly opening valve having a centrally domed portion slidably mounted on said stud, and an inwardly opening valve housed within said central dome.

4. In a filling spout closure of the character described, a retainer cap having a centrally dependent stud, a first domed member comprising a cylindrical portion, an upper inturned flange slidably carried on said stud and a lower outturned ange, a sealing gasket bearing on the last mentioned ange, a second domed member comprising a cylindrical portion fitted interiorly of the cylindrical portion of the rst mentioned member, a lower outturned flange cooperating with the rst mentioned outturned flange to retain said gasket and an upper inturned flange af fording a valve seat, a valve for said seat housed within the second domed member and a retainer for said valve engaging a seating formation in the cylindrical portion of the second domed member.

5. In a lling spout closure o f the character described, a retainer cap having a centrally dependent stud, a first domed member comprising a cylindrical portion, an upper inturned flange slidably carried on said stud and a lower outturned flange, a sealing gasket bearing on the last mentioned flange, a second domed member comprising a cylindrical portion fltted interiorly of the cylindrical portion of the first mentioned member, a lower outturned flange cooperating with the rst mentioned outturned flange to retain said gasket and an upper inturned flange affording a valve seat, a valve for said seat housed within the second domed member and a coil spring engaging said valve at one end and engaging at its other end a seating formation in the cylindrical portion of the second domed member.

6. In a pressure system, a ller spout having a valve seat and a vent beyond said seat, a closure cap removably secured to the spout and having a dependent central stud, a spring pressed valve member having a central dome portion loosely mounted on said stud and an upwardly flaring flange to engage said seat in self-centering relation.

7. A iiller assembly including a spout having a pair of spaced seats and a vent between the seats, a removable spout closure including a cap having detachable connection with the spout, a' spring diaphragm sealingly engaging the outermost spout seat, a vdependent stud carried by the 5 wardly opening valve means housed within the domed portion of said valve.

8. In a cooling system, a vented ller spout.

having a valve seat, a closure cap removably connected to the spout and provided with a de- 10 pendent stud, a spring pressed valve to engage said seat and having a central dome portion loosely mounted on said stud, a valve seat within said domed portion, a normally open valve associated with said seat to enable system breathing through the vent and to close against rapid liquid or vapor flow, and a retainer device supporting said valve in its open position. 

